Solar sailer

Solar sailers were a method of propulsion used by some starships. Although called "solar" sailers, they were more commonly propelled by tachyon streams and ultraviolet lasers rather than the photons and "solar wind" (high-energy plasma which escaped a star's gravity) of sunlight. Gathered on a sufficiently large surface (solar sails would unfurl to colossal diameters, rivaling the surface area of moons), the absorbed momentum would then accelerate the spacecraft. Once optimal velocity had been reached, the hyperdrive motivator would kick in and allow the craft to enter hyperspace.[1]

While cheap and easy to produce, solar sails were not widely used as a propulsion system, for three main reasons: the first was that the sail was at its most efficient when traveling close and directly away from a star. Solar wind and photons were only exploitable in the general vicinity of a star, and changing directions would imply either the use of gravity from a nearby stellar object, or the inclination of the whole sail. The second reason was the sail's size: even a small ship would require a very large sail to be accelerated to hyperspace entry velocity, thus increasing the overall ship's size. This could be averted to a point by storing the sail away when not in use. The third reason was that the sail was rather fragile: micrometeorites and random stellar debris could very quickly and irremediably shred a solar sail to the point of uselessness.[source?]

A major advantage of the solar sail, however, was that since it used no on-board fuel, it left no readily identifiable residues, and its passage was virtually undetectable once the ship had departed.